The authors are thankful to the Chairman, Department of Geology, AMU, Aligarh for providing the facilities. Dr. V. Balaram, National Geophysical Research Laboratory, Hyderabad and Dr. N. K. Saini, Wadia Institute of Himalayan Geology, Dehra Dun are thanked for providing analytical facilities. Financial assistance by the DST, Govt. of India to carry out this work (SR/S4/ES-180/2005) is duly acknowledged. We express our sincere thanks to Prof. Talat Ahmad for inviting us to contribute to this special volume. We are grateful to Prof. D.K. Paul, Prof. Rajesh K. Srivastava and Dr. Vivek K. Malviya for constructive and helpful reviews and suggestions that led to considerable improvements in the final version of the manuscript.